Shawn Brimley, a senior Pentagon and White House official who pressed the U.S. military to embrace a future of increasingly rapid technological change, died Jan. 9 at a hospital in Bethesda, Md. He was 40.
The cause was complications from colon cancer, said Colin Kahl, a friend.
Mr. Brimley was most recently vice president and director of studies at the Center for a New American Security, a defense and foreign policy think tank that produced many of the top officials at the Pentagon and State Department during the Obama administration.
He served in the government from 2009 to 2012, first as a special adviser at the Pentagon and then as director of strategic planning at the National Security Council. Otherwise, much of his Washington career was spent at CNAS.
As a White House official and later at CNAS, Mr. Brimley pushed the military to prepare for a new era of robotic warfare. His ideas helped drive the Pentagon's "third-offset strategy," which sought to reshape the U.S. military in preparation for a possible conflict with a major power such as Russia or China.
The concept, which originated with a CNAS study that Mr. Brimley co-authored, was announced by then-Defense Secretary Chuck Hagel in 2014 as Pentagon policy. It presumed that the United States would be badly outnumbered in a regional conflict with China or Russia and would need to use its technological advantages to offset its enemies' quantitative superiority.
The strategy harked back to the Cold War, when the U.S. military sought to offset the Soviet Union's greater manpower with investments in nuclear weapons to deter Moscow. Later, the U.S. military made big investments in stealthy, deep-strike aircraft, precision bombs and missile systems capable of hitting rear-echelon Soviet forces.
Together with Deputy Defense Secretary Robert Work, Mr. Brimley envisioned that the United States would be able to use swarms of drone aircraft, undersea robotics and rapid advances in artificial intelligence to overcome a massive enemy force.
"He and Bob Work saw a coming competition with Russia and China as great powers and recognized that the U.S. could not stand still and retain its advantage," said Michele Flournoy, undersecretary for policy in the Pentagon under Obama and a former chief executive at CNAS.
The third-offset strategy also foresaw a future in which advanced Chinese missiles would push vulnerable U.S. aircraft carriers further out to sea. Driven by the new strategy and the Chinese threat, the Pentagon is starting to invest in unmanned bombers and aircraft-carrier-capable drones that can strike from longer ranges than conventional aircraft.
Shawn William Douglas Brimley was born in the Toronto suburb of Mississauga on June 27, 1977. After serving five years in the Canadian army, he graduated in 2001 from Queen's University in Kingston, Ontario, and received a master's degree in security policy studies in 2007 from George Washington University.
Mr. Brimley's father was an engineer who worked in the Canadian space program and was twice a finalist for the country's astronaut corps. The two shared a passion for military strategy and technology. Mr. Brimley's father recalled his son saying as a teenager that he wanted to be "a strategic analyst."
In 2007, Mr. Brimley became one of the founding employees at CNAS. He was sworn in as a U.S. citizen before entering the Obama administration.
Mr. Brimley often described himself as a "think-tank nerd." At a time when government service is often disparaged, he embraced work in U.S. national security as a calling. "Maybe because he was an immigrant, he really believed in the power of American leadership and America's unique role in the world," said Derek Chollet, his boss in the White House. "There was that idealism about him."
Former colleagues recalled Mr. Brimley's goofy sense of humor. He bought an elaborate, sports-mascot-like parrot suit for a Halloween party. For a CNAS Christmas party, he dressed up as Santa Claus and then ordered the think tank's president, Richard Fontaine, to sit on his lap and tell him whether he had been "naughty or nice." Mr. Brimley would surprise colleagues at work by hiding behind a corner and taking shots at them with a Nerf gun as they tried to work, co-workers recalled.
"Brimley was a policy wonk's idea of a policy wonk," a friend, Andrew Exum, wrote in an essay for the Atlantic.
Survivors include his wife of 13 years, Marjorie Clark Brimley, and their three children, Claire Brimley, Austin Brimley and Tommy Brimley, all of Washington; his parents, Sheryll and Bill Brimley of Ontario; and two sisters.
Former colleagues said that one of Mr. Brimley's most important contributions had been encouraging younger people to pursue national security as a profession.
"He was engaging and self-deprecating, with a borderline inappropriate sense of humor," said Kahl, a onetime national security adviser to vice president Joe Biden. "It was really easy for younger people to relate to him. He believed strongly in public service, no matter who the president."
CORRECTION: An earlier version of the story said that Mr. Brimley died at his home in Washington. The story has been revised.